1$ Wireless Device to Control Arduino From Anywhere

#DTMF stands for DUAL TONE MULTIPLE FREQUENCY , in which we are going to use Mobile phone to make its as a wireless device, it works on the frequency which we generate on keypad of caller phone.

Supplies:

Step 1: How It Works?

There are two frequency groups in keypad of mobile phone ,combination of these two will form Dual tone multiple frequency ,in simplewords by adding or mixing two or more frequenciesgenerates DTMF tone.

Step 2: Output of DTMF Module !

Observe the pics ,Here we get a tone from our cellphone by using aux wire toDTMF Decoder IC namely MT8870 which decodes the toneinto digital signal of 4bit.

whenever we press any key on keypad of mobile we get different output which is indicated by using LEDs on module , if you look at the images carefully you can find different output for different keys

Step 3: Interfacing It to Arduino

Arduino UNO is used for controlling whole process ,Arduino reads commands sent byDTMF Decoder and compare with define code or pattern.here we connect Digital io pins of Arduino to the Output pins of DTMF module .